Package structure

ABSTRACT

A package structure, comprising: a substrate, having at least one conductive units provided at a first surface of the substrate; at least one first die, provided on a second surface of the substrate; a connecting layer; a second die, provided on the connecting layer, wherein the connecting layer comprises at least one bump for connecting the first die to the second die such that the first die and the second die are electrically connected; and at least one bonding wire, for electrically connecting the first die to the conductive units or the substrate.

BACKGROUND

A wide I/O memory device is a memory device having pins more than other kinds of memory devices. The wide I/O memory device can have a rapid data accessing speed, since it has large number of pins to access data.

FIG. 1 is a cross sectional diagram illustrating a semiconductor structure for a related art wide I/O memory device. As shown in FIG. 1, the wide I/O memory device 100 has a memory cube MC and a logic die LI provided on a substrate Su. The memory cube MC comprises a plurality of memory dies MI. Vias VA (only one is marked by the symbol) are generated via a TSV (Through-Silicon Via) process, such that the memory cube MC and a logic die LI can be electrically connected to the conductive units Cu (ex. solder ball) or the substrate Su. However, the I/O memory device needs plenty of vias since it has many pins, but the TSV process causes high cost. Therefore, the cost for the I/O memory device is extremely high.

SUMMARY

Therefore, one objective of the present application is to provide a package structure that can be generated without the TSV process.

One embodiment of the present application discloses a package structure, comprising: a substrate, having at least one conductive units provided at a first surface of the substrate; at least one first die, provided on a second surface of the substrate; a connecting layer; a second die, provided on the connecting layer, wherein the connecting layer comprises at least one bump for connecting the first die to the second die such that the first die and the second die are electrically connected; and at least one bonding wire, for electrically connecting the first die to the conductive units or the substrate.

In view of above-mentioned embodiments, a package structure can be produced without performing TSV processes. Therefore, the cost can be largely reduced.

These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross sectional diagram illustrating a semiconductor structure for a related art wide I/O memory device.

FIG. 2 is a cross sectional diagram illustrating a package structure according to one embodiment of the present application.

FIG. 3 is a cross sectional diagram illustrating detail structures for the embodiment shown in FIG. 2 of the present application.

FIG. 4-FIG. 8 are cross sectional diagrams illustrating a package structure according to different embodiments of the present application.

DETAILED DESCRIPTION

The package structure according to the present application will be explained for detail below. Please note the package structure according to the present application is not only can be applied to the above-mentioned wide I/O memory device, but also can be applied to other electronic devices.

FIG. 2 is a cross sectional diagram illustrating a package structure 200 according to one embodiment of the present application.

As shown in FIG. 2, the package structure 200 comprises a substrate Su, a first die DI₁, a connecting layer BL, a second die DI₂ and at least one bonding wire WB. The substrate Su having at least one conductive unit Cu (only one of them is marked by a symbol) provided on a first surface S₁ thereof. The first die DI₁ is provided on a second surface S₂ of the substrate Su. The connecting layer BL is provided on the first die DI₁, and is for electrically bumping the first die DI₁ to the second die DI₂. In one embodiment, the connecting layer BL comprises at least one bump for electrically connecting the first die DI₁ to the second die DI₂. The at least one bonding wire WB is for connecting the first die DI₁ and the conductive units Cu, or connecting the first die DI₁ and the substrate Su. In one embodiment, the bonding wire WB is connected to via V formed in the substrate Su, which is electrically connected to the conductive unit Cu, but is not limited. Also, in the embodiment illustrated in FIG. 2, the size of the first die DI₁ is larger than which of the second die DI₂.

FIG. 3 is a cross sectional diagram illustrating detail structures for the embodiment shown in FIG. 2 of the present application. As shown in FIG. 3, the first die of the package structure 300 is a memory die MDI and the second die is a logic die LDI. Please note the kinds of dies can be swapped. That is, the first die can be a logic die LDI and the second die can be a memory die MDI. Additionally, in one embodiment the connecting layer BL is generated via a flip chip process. In another embodiment, the connecting layer BL comprises a metal layer ML located between the memory die MDI and the logic die LDI, and at least one micro bump BM for connecting the memory die MDI and the logic die LDI. Also, in such embodiment, the metal layer ML is a redistribution layer (RDL). Please note the package structure according to the present application can include only part of the structures described in FIG. 3. For example, the first die and the second die can be other kinds of dies besides the memory die and the logic die, but the connecting layer BL can still comprise a metal layer ML, and the micro bump BM.

FIG. 4-FIG. 8 are cross sectional diagrams illustrating a package structure according to different embodiments of the present application.

In FIG. 4, the package structure 400 comprises more than one first die DI₁ located between the connecting layer BL and the substrate Su. If the package structure 400 is a wide I/O memory device, the first dies can be memory dies to form a memory cube.

In the package structure 500 of FIG. 5, the sizes of the first die DI₁ and the second die DI₂ are the same, and the connecting layer BL has a first touch side DCS₁ and a second touch side DCS₂. The first touch side DCS₁ contacts a first surface Sr₁ of the first die DI₁ and the second touch side DCS₂ contacts a second surface Sr₂ of the second die DI₂. Also, in FIG. 5 an area of the first touch side DCS₁ is smaller than which for the first surface Sr₁ of the first die DI₁, and an area of the second touch side DCS₂ equals to which for the second surface Sr₂ of the second die DI₂.

The structure shown in FIG. 6 is almost the same as which of FIG. 5, one difference is that the area of the second touch side DCS₂ equals to which for the second surface Sr₂ of the second die DI₂ for the package structure 500 in FIG. 5, but the area for the second touch side DCS₂ is smaller than which for the second surface Sr₂ of the second die DI₂ for the package structure 600 in FIG. 6.

In the embodiments described in FIG. 7 and FIG. 8, the sizes of the first die DI₁ and the second die DI₂ are the same as well, but the location for the first die DI₁ or the second die DI₂ is shifted such that a projected image of the second die DI₂ does not totally contain the first die DI₁. In the embodiment described in FIG. 7, bonding wire WB is only provided to one side of the first die DI₁. In the embodiment described in FIG. 8, bonding wires WB are provided to two sides of the first die DI₁.

Please note the structure illustrated in FIG. 3 can also be applied the embodiments described in FIG. 4-FIG. 8.

In view of above-mentioned embodiments, a package structure can be produced without performing TSV processes. Therefore, the cost can be largely reduced.

Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. 

What is claimed is:
 1. A package structure, comprising: a substrate, having at least one conductive units provided at a first surface of the substrate; at least one first die, provided on a second surface of the substrate; a connecting layer; a second die, provided on the connecting layer, wherein the connecting layer comprises at least one bump for connecting the first die to the second die such that the first die and the second die are electrically connected; and at least one bonding wire, for electrically connecting the first die to the conductive units or the substrate; wherein the connecting layer has a first touch side and a second touch side, wherein the first touch side contacts a first surface of the first die and the second touch side contacts a second surface of the second die, where an area of the first touch side is smaller than an area for the first surface of the first die; wherein an area of the second touch side equals to an area for the second surface of the second die.
 2. The package structure of claim 1, wherein the first die is a memory die and the second die is a logic die.
 3. The package structure of claim 1, wherein the first die is a logic die and the second die is a memory die.
 4. The package structure of claim 1, wherein a size of the first die is larger than a size of the second die.
 5. The package structure of claim 1, wherein a size of the first die equals to a size of the second die.
 6. The package structure of claim 5, wherein a projected image of the second die does not totally contain the first die.
 7. The package structure of claim 6, wherein the bonding wire is provided at one side of the first die.
 8. The package structure of claim 6, wherein the bonding wire is provided at two sides of the first die.
 9. The package structure of claim 5, wherein a location for the first die or the second die is shifted.
 10. The package structure of claim 9, wherein the bonding wire is only provided to one side of the first die.
 11. The package structure of claim 9, wherein the bonding wires are provided to two sides of the first die.
 12. The package structure of claim 1, wherein the connecting layer is generated via a flip chip process. 